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About Hawaiian Monk Seals

In 1976, the Hawaiian monk seal (Monachus schauinslandi) was listed as an endangered species. Today, more than 30 years later, it has the unfortunate status as the most endangered pinniped in the United States.

Hawaiian Monk Seal KP2
© NOAA Permit #932-1489-09


The Hawaiian monk seal population has declined at a rate of three to four percent per year over the past decade, recently reaching a low of fewer than 1,100 Hawaiian monk seals left in existence. Moreover, a newborn monk seal has only a one-in-five chance of surviving to adulthood. This is dismal news for a species found only in Hawaii and that has been in existence for more than 15 million years.

There are some hopeful signs on the horizon however. Significant efforts have been made to enhance the recovery of the species in the past few years, including the removal of several tons of ocean trash from monk seal habitat and translocating animals from low survival areas to higher survival areas.

Early indications are that the hard work is paying off. National Oceanic and Atmospheric Administration (NOAA) teams reported 121 monk seal pups were born in the 2014 season, compared with 103 pups in 2013 and 111 pups in 2012. The total population is now estimated to be around 1,200.

Of these, approximately 150 are in the Main Hawaiian Islands, and 1,050 are in the Northwestern Hawaiian Islands. For reasons such as shark predation, food shortages and marine debris, the monk seals on the Northwestern Hawaiian Islands are having a harder time than their counterparts on the Main Islands. However, the seals on the Main Islands are also increasingly victims of marine debris and other negative human interactions, such as gun shots and harassment.

Some facts about the Hawaiian monk seal:

  • The Hawaiian Monk Seal is the official state mammal of Hawaii. 
  • Hawaiian monk seals have a diet that consists mainly of fish, squid, octopus, and lobster.
  • They hunt mainly at night and often haul out on sandy beaches during the daytime.
  • Mating season is from December until mid-August.
  • Pups are approximately three feet long at the time of birth and weigh about 35 pounds. They spend their first 35 to 40 days with their mother while they nurse.
  • Most Hawaiian monk seals are found in six main breeding subpopulations in the Northwestern Hawaiian Islands (NWHI): Kure Atoll, Midway Islands, Pearl and Hermes Reef, Lisianski Island, Laysan Island, and French Frigate Shoals.
  • Hawaiian law makes it a felony to harm a Hawaiian monk seal. Violators face fines up to $50,000.

You can make a difference to ensure the survival of the Hawaiian monk seal!
Consider a donation to save this endangered species.

Related links:

Learn more about Hawaiian Monk Seals.

Read how The Marine Mammal Center is Working with Endangered Species.

View the Hawaiian Monk Seal Historical Timeline from NOAA Fisheries.


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